1. Field of the Invention
This invention relates to a process for the continuous production of a precursor of alumina fiber.
2. Description of the Prior Art
Heretofore various processes and apparatus have been proposed for the production of alumina fiber. For example, British Pat. No. 1,360,197 teaches an apparatus for the production of rayon fiber. During operation of the apparatus a solution is extruded through a spinneret with about 400 micron diameter dies and is blown with the air discharged through two nozzles that are disposed so as to converge at an angle of about 30.degree. in the direction of air blowing.
For the invention of this British patent to permit effective mass production of rayon fiber, installation of a multiplicity of extruders in a plurality of rows is necessary. Because of the restrictions arising from the nature of the apparatus designed primarily for the production of rayon fiber, the mat of alumina fiber to be produced by this apparatus assumes the form of a laminate of thin webs and therefore is quite susceptible to separation into individual webs of the laminate. Thus, the alumina fiber mat in its unmodified form cannot be effectively used as a lining material for furnaces. To serve advantageously as the lining material, the alumina fiber must be used in the form of a blanket mixed with rayon fiber.